There are many circumstances in industry and elsewhere where remote sensing of objects and locations is desired for some reason. Optical sensing for monitoring and other purposes of remote locations has for the most part relied on visual observation, sometimes with the aid of magnifying optical instruments or by using video cameras for display on monitors and like devices. Although the size of such video electronic equipment has over time been reduced, overall such devices still are relatively bulky and inappropriate for many applications and do not provide means for distinguishing between objects of different colors or intensities except possibly by visual observation. No one device known so far has provided sense images for the purpose of producing an image that can be made to be otherwise sensed such as by feel. Fiber optic means are an efficient means of remotely communicating such optically sensed images and information and can be combined with means for forming a tactile or other representation of such images and information.
The present invention also lends itself to helping visually impaired people face the difficult challenge of recognizing remote images in their surrounding environment. Although they can and to utilize external guide mechanisms such as seeing eye dogs and canes which help them to avoid hazards, there still are times when undetected hazards put them at risk. Also, published and other types of information not in the Braille format cannot be comprehended by those with such visual impairment. Therefore, an optical display device which enables one to rapidly experience their surroundings in a tangible manner without coming in direct contact with surrounding objects can be an important instrument.
Several different forms of optical devices for producing a physical representation of a visual image have been designed in the past. The reading aid disclosed in U.S. Pat. No. 3,229,387 displays visual images in a vibrating physical display. Visual images are focused through a lens or through fiber optic means onto a system of photoconductive cells which produces and applies an unamplified current to a plurality of piezoelectric reeds. These reeds vibrate when activated to form the vibrating display. The visual substitution system disclosed in U.S. Pat. No. 3,562,408 incorporates a photomultiplier tube with a photocathode, an image intensifier and an anode display array which imparts a current representing the images directly into the skin of the wearer. An electrical optical scene scanner is disclosed in U.S. Pat. No. 3,594,787 which focuses images onto a photosensitive cell and displays an amplified electrical signal to individual display elements to provide a raised surface representing the observed image. None of these inventions convert the received incoming images into amplified laser light signals which in turn are used to produce representative physical images on a light sensitive display device.
The present invention is directed to a device which can convert incoming visual and other signals observed by sensing means into physical, tactile displays. Importantly unlike the prior art devices, the present apparatus converts incoming images into corresponding light energy signals such as in the form of amplified laser light signals, which energy signals are directed to light sensitive elements in a device that produces tactile displays. When the optical display device is used, the image input portion of the apparatus is directed towards the object or objects of interest and the input energy signals produced are converted thereby into amplified laser light signals by circuits comprising in part photosensitive means and laser diodes. The device includes a plurality of conversion and amplification circuits corresponding in number with the number of individual signal transmitting means, and with the corresponding number of display elements in the display device. The resulting amplified laser light signals are optically transmitted through fibers in a coherent optical bundle of fibers towards individual movable elements formed in an array on the photosensitive display device. A coherent fiber optic bundle is a bundle wherein each of the fibers are physically in the same position or location in the bundle, including the position at both opposite ends of the fiber bundle, so the portions of the viewed image transmitted by the individual fibers are in an identical arrangement or orientation when the image enters and exits the fiber bundle. The display elements may be treated with an optically absorbant coating which responds to the incoming laser light energy by causing an element displacement sufficient to form a tactile or three dimensional representation of the observed images. This invention enables one to physically detect objects in the field of view and to communicate such information that otherwise would not normally be able to be seen or sensed in certain situations. The device can be useful as an aid to the blind and also for use in certain manufacturing processes and other fields where analysis of observed information is required and where remote information gathering even on a continuous basis is required.